package com.shuang.dp16;

import java.util.*;

class Main{
    public static void main(String [] args){
        Scanner sc = new Scanner(System.in);
        int m, n;
        while (sc.hasNextInt()) {
            // 从键盘输入参数，中间用空格隔开
            n = sc.nextInt();
            m = sc.nextInt();

            // 求排列问题，先遍历背包再遍历物品
            int[] dp = new int[n + 1];
            dp[0] = 1;
            for (int j = 1; j <= n; j++) {
                for (int i = 1; i <= m; i++) {
                    if (j - i >= 0) dp[j] += dp[j - i];
                }
            }
            System.out.println(dp[n]);
        }
    }
}